| Titre : |
Graft polymerization. IV. Further studies of the initiation step in the graft polymerization of vinyl monomers onto chrome-tanned collagen |
| Type de document : |
texte imprimé |
| Auteurs : |
Maryann M. Taylor, Auteur ; Edward H. Harris, Auteur ; Stephen H. Feairheller, Auteur |
| Année de publication : |
1977 |
| Article en page(s) : |
p. 294-312 |
| Note générale : |
Bibliogr. |
| Langues : |
Américain (ame) |
| Catégories : |
Collagène
Copolymères greffés
Cuirs et peaux
polymères vinyliques
Polymérisation
Tannage au chrome
|
| Index. décimale : |
675 Technologie du cuir et de la fourrure |
| Résumé : |
In the process for the graft polymerization of vinyl monomers onto chrome-tanned collagen developed at the Eastern Regional Research Center, redox initiation with the persulfate-bisulfite combination is a key step. Various aspects of this reaction have now been examined and the results obtained permit improving the grafting and monomer conversion efficiencies. As monitored by iodometric titration, the partition of persulfate ion between water and collagen depends upon the per-sulfate ion concentration and the chrome content of the collagen. The rate of disappearance of persulfate ion from solution and the quantity absorbed increased with higher concentrations of persulfate ion or chrome content of the collagen. The implication is that both a mass action effect and ionic attraction are involved. Similar bisulfite ion distribution results were obtained in studies with a radioactive isotope of sulfur. In addition, monomer absorption was studied with the chrome-tanned collagen. All of these studies indicated that grafting takes place f rom monomer in the aqueous phase onto free radical sites generated on the collagen by the absorbed redox initiation system. Additional studies with different reducing agents used at varying molar ratios to the persulfate ion clearly indicated an optimum ratio which gave both maximum monomer to polymer conversion and grafting. The persulfate-bisulfite combination still appears to he the best. |
| Note de contenu : |
- EXPERIMENTAL : Materials - Chrome tanning and analyses - Depickling procedure - Persulfate partition study - Bisulfite partition procedure - Free radical partition study - Graft polymerization on stock containing various amounts of CrO3 - Monomer partition
- RESULTS AND DISCUSSION : Persulfate ion partition - Sodium bisulfite partition studies - Various reductants and molar ratio studies - Identification of the method of graft formation - Chrome-graft polymerization study - Monomer partition study
- Table 1 : Cr2O3 fixed by untreated skins
- Table 2 : 35S-tagged NaHSO3 partition study
- Table 3 : Reducing systems and molar ratios studied
- Table 4 : Effect of free radical partition on polymer analysis
- Table 4 : Effect of chrome content on polymer content of grafted leather |
| En ligne : |
https://drive.google.com/file/d/19vEmOZqyns4hwa2KvTEQth101xN3GPsU/view?usp=drive [...] |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38264 |
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXII (Année 1977) . - p. 294-312
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Graft polymerization. IV. Further studies of the initiation step in the graft polymerization of vinyl monomers onto chrome-tanned collagen in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXII (Année 1977)
